The present invention relates to connectors, in particular connectors for active implantable medical devices.
Although the invention will be mainly described in the context of a pacemaker, it should be understood that this is only one exemplary embodiment of an invention that is applicable in a much more general way to a variety of xe2x80x9cactive implantable medical devicesxe2x80x9d, as such devices are defined by the Jun. 20, 1990 Directive 90/385/CE of the Council of the European Communities. These devices thus include, in addition to pacemakers, and among other devices, defibrillators, cardiovertors, neurological apparatus, pumps for diffusion of medical substances, cochlear implants, and implanted biological sensors.
Active implantable medical devices typically comprise a generator containing the electronics of the device that are connected electrically and mechanically to a probe, with the connection being realized by the surgeon at the time of the implantation. More specifically, the generator includes a case, containing the various electronic circuits and the power source of the device, and a connector head that is mechanically and electrically connected to the case. The connector head also is equipped with one or more cavities able to receive the probe(s).
The manufacture of the generator device generally comprises stages including initially, producing the complete case, containing the electronics and power source, the case having an upper face through which a plurality of feed-through leads are present. The feed-through leads are connected at one end to the electronic circuits within the case and are intended to be connected at one end to corresponding terminals of the connector head. The terminals in turn couple to the conductors of the external probe(s). The feed-through leads extend out through the face of the case in an xe2x80x9cinsulating traversexe2x80x9d structure, i.e., posts made of an insulating material that are fixed (e.g., welded) on the case.
Until now, the connector head has been generally assembled by connecting the various terminals to the corresponding feed-through leads, and then immersing the whole assembly in a molded silicone resin, ensuring at the same time the protection of the elements of the head, the sealing between head and case, and the definition of the cavities, coming from the molding, that are to receive the connecting (and conducting) extremities of the probes.
This technique of simultaneous assembly of all the elements of the head and of molding of the complete assembly is a proven and economic method, but it presents a certain number of disadvantages. One disadvantage is a lengthy time of manufacture, because it is necessary to await the complete drying of the silicone adhesive. Another disadvantage is a relatively larger volume needed for the connector head, because of the molding which comes to cover all the parts of the head. Yet another disadvantage exists in the event that a defect is discovered after the molding step, because it is impracticable, if not impossible, simply to separate the connector head from the case, isolate the defective part, and re-work the assembly.
Another manufacturing technique is known in which the connector head is made of a rigid material, for example, an epoxy resin or a polyurethane derivative such as Tecothane(trademark). The case is then equipped with elastic claws with hooks that cooperate with homologous slits in the connector head, whose form allows a deployment of the claw hooks at the installation of the connector head to the case. This technique, although it makes it possible to reduce the time of manufacture, still presents the disadvantage of the impossibility of separating the connector head from the case once the generator assembly is made.
It is, therefore, an object of the present invention to provide a generator assembly including a connector head that has a reduced time of manufacture.
It is another advantage to provide a connector head that has a reduced volume.
It is yet another advantage to provide a connector head that has a possibility of separating the connector head from the case after assembly.
It is still another advantage to provide a connector head that has the possibility of controlling, piece by piece, the various elements of the operability of the structure of the connector.
It is another advantage to provide a connector head that has a reduced number of pieces necessary to allow the mechanical anchoring of the connector head.
To this end, the present invention proposes an active implantable medical device such as a pacemaker, a defibrillator and/or a cardiovertor, including: a case comprising a face through which a series of conducting feed-through leads emerge, the feed-through leads being connected to the internal circuits of the case; a connector head comprising a rigid insulating material, able to receive terminals of electrical contact; and a mechanical connection component, able to solidarize (interconnect) the case with the connector head, wherein the connection component is a removable component and on removal allows the separation of the connector head from the case after the initial solidarisation of the two parts.
Advantageously, the case also comprises at least one element able to cooperate with the connection component. This cooperating element is of a homologous form with that of the connection component at the point(s) of mutual contact. More preferably, the cooperating element is a surface feature or area, for example, a peripheral groove, in an insulating traverse carrying the conducting feed-through leads. Thus, the mechanical connection element is engaged with the connector head and the insulating traverse of the case, interconnecting the two elements together.
In a first embodiment, the mechanical connection component is an elastically deformable component able to cooperate with the aforementioned homologous cooperating element of the case by a click-and-ratchet mechanism, in particular, a clamp that is able to cooperate by two opposed ends with at least two insulating traverses of the case bearing the conducting feed-through leads. The clamp also cooperates with an aperture such as a slot in the connector head when engaged with the traverses to form the interconnection.
In a second embodiment, the mechanical connection component is a rigid component able to cooperate with the aforementioned homologous cooperating element of the case by an adjusted engagement, for example, a pin that is able to cooperate with an aperture such as a hole in the connector head, and a surface feature, such as a groove or an aperture in the insulating traverse of the case bearing the conducting feed-through leads.